As footballing rivalries go Chelsea and Brentford has always seemed more of a London-style neighbourly acquaintance, two clubs separated by a six-mile stretch of west London tangle who, on the pitch, are still on no more than friendly nodding terms. The visit of Chelsea to Griffin Park in the FA Cup on Sunday lunchtime is the first time the clubs have met in anger since 1950. If this was always going to stand out as one of the ties of the fourth round, this is in part a function of the peculiarly fraught sense of reckoning that has hovered above Rafael Benítez's high-stress interim Chelsea tenure ever since his appointment nine weeks ago. At his unveiling Benítez made much of the five "big opportunities" for silverware this season: with the Europa League likely to be soft-pedalled, the Cup now represents the most realistic opportunity of a trophy for these lame‑duck European champions.

Beyond the familiar Fulham Road operetta the visit of the holders to their League One neighbours is simply a deliciously intriguing FA Cup tie, a tribute to the January gifts the competition can still scatter about when the draw is kind. It is a match that also comes at a significant time for Brentford, currently engaged in one of their periodically hopeful upswings under the guidance of Uwe Rösler and the ambitious ownership of the online gambling tycoon Matthew Benham. Rösler was, of course, a popular hero of the pre-jackpot Manchester City, with a passion for the English game that stretches back to his school days in Leipzig when Rösler and his fellow pupils would listen to tapes of English football crowds and marvel at the fervour of that vanished terrace culture. Two years – and three Chelsea managers – on from his surprise appointment, he is now thoroughly settled at west London's most pleasantly suburban football league bantamweight.

"I didn't expect to get the job," Rösler says now. "The owner is involved in the Next-Gen [the junior European competition] and has a natural interest for European football. He wanted a manager from outside the box and I am very thankful for that."

If Rösler is realistic about the challenge facing him, there is beneath his caution a sense of genuine conviction that his neat, slick-passing Brentford team, who are third in League One, have both the discipline and the tactical sense to cause Chelsea problems. "We are not turning up just for the occasion," he says. "We want to give them a game. The focus is going in and trying to win. It is difficult and we are massive outsiders but we have the mentality at this football club to go into every game to win. If you're thinking about shirts or pictures or whatever, you have already lost."

While Rösler is warm in his support for his opposite number, there is still some encouragement to be taken in the fug of home-fan hostility that has coloured Benítez's appearances at Stamford Bridge and which may yet accompany him on the six-mile journey west. Certainly keeping the visitors at bay for as long as possible could be key to inducing an attack of creeping banana-skin anxiety to follow the recent second-half fade against Southampton, Swansea and Arsenal.

"I'm not thinking about my colleague Rafa," Rösler says. "I'm thinking about my players and how we can compete against a team full of world stars. I always think any manager and a group of players like to be supported, especially by your own supporters. It is extremely difficult working conditions when you lead the team in your own stadium and you feel your own supporters are not supporting you 100%."

Understandably, as both a retired centre-forward and a manager whose youthful defence must address the challenge of a hit-and-miss £50m striker, Rösler has had a particular eye on Fernando Torres in his preparations. "I saw him against Arsenal and his movement in the first 20 minutes was unbelievable. Unfortunately then he had one bad touch, or he missed one bad chance in the first half and you felt like it goes a little bit away from him. I was a striker who lived a lot for movement and his movement is fantastic. He is a proven world star: he works so hard, people forget that. But everyone compares him with Drogba."

Either way it promises to be a bravura occasion at Griffin Park, a ground menaced for the past few years by plans for redevelopment on a nearby vacant site, but now expecting its largest crowd since the mid-1980s, with all four sides of this low-rise corrugated arena a sell-out.

If the optimism of Brentford's manager can percolate beyond the touchline it could yet be an extraordinary Sunday lunchtime in west London: "We need an extraordinary day, we need luck, we need players who play over their normal capacity. If we stay as long as we can in the game, the longer the game goes our chances will go up. That is what I'm focusing on."